如何从二维数组元素PHP中检查空的单个数组元素答案

【问题标题】：How to check empty single array element from 2D array elements PHP如何从二维数组元素PHP中检查空的单个数组元素
【发布时间】：2015-08-24 00:41:31
【问题描述】：

我知道这个问题被问了很多次，我已经搜索了足够多的内容来找到我的结果，但到目前为止还没有成功。

假设我有这种类型的数组：

1 ~~~
1 ###
Array ( [macro_ratio] => 1.1 [foodCategoryId] => 37 ) @@@
2 ###
Array ( [macro_ratio] => 1.2 [foodCategoryId] => 2 ) @@@
3 ###
Array ( [macro_ratio] => 1.3 [foodCategoryId] => 3 ) @@@
4 ###
Array ( [macro_ratio] => [foodCategoryId] => 4 ) @@@
5 ###
Array ( [macro_ratio] => [foodCategoryId] => 5 ) @@@
6 ###
Array ( [macro_ratio] => [foodCategoryId] => 6 ) @@@
7 ###
Array ( [macro_ratio] => [foodCategoryId] => 7 ) @@@
8 ###
Array ( [macro_ratio] => [foodCategoryId] => 8 ) @@@
9 ###
Array ( [macro_ratio] => [foodCategoryId] => 9 ) @@@
10 ###
Array ( [macro_ratio] => [foodCategoryId] => 38 ) @@@
11 ###
Array ( [macro_ratio] => [foodCategoryId] => 10 ) @@@
12 ###
Array ( [macro_ratio] => [foodCategoryId] => 11 ) @@@
13 ###
Array ( [macro_ratio] => [foodCategoryId] => 12 ) @@@
14 ###
Array ( [macro_ratio] => [foodCategoryId] => 13 ) @@@
15 ###
Array ( [macro_ratio] => [foodCategoryId] => 14 ) @@@
16 ###
Array ( [macro_ratio] => [foodCategoryId] => 15 ) @@@
17 ###
Array ( [macro_ratio] => [foodCategoryId] => 16 ) @@@
18 ###
Array ( [macro_ratio] => [foodCategoryId] => 17 ) @@@
19 ###
Array ( [macro_ratio] => [foodCategoryId] => 39 ) @@@
20 ###
Array ( [macro_ratio] => [foodCategoryId] => 18 ) @@@
21 ###
Array ( [macro_ratio] => [foodCategoryId] => 19 ) @@@
22 ###
Array ( [macro_ratio] => [foodCategoryId] => 20 ) @@@
23 ###
Array ( [macro_ratio] => [foodCategoryId] => 21 ) @@@
24 ###
Array ( [macro_ratio] => [foodCategoryId] => 22 ) @@@
25 ###
Array ( [macro_ratio] => [foodCategoryId] => 23 ) @@@
26 ###
Array ( [macro_ratio] => [foodCategoryId] => 24 ) @@@
27 ###
Array ( [macro_ratio] => [foodCategoryId] => 25 ) @@@
28 ###
Array ( [macro_ratio] => [foodCategoryId] => 40 ) @@@
29 ###
Array ( [macro_ratio] => [foodCategoryId] => 41 ) @@@
30 ###
Array ( [macro_ratio] => [foodCategoryId] => 26 ) @@@
31 ###
Array ( [macro_ratio] => [foodCategoryId] => 27 ) @@@
32 ###
Array ( [macro_ratio] => [foodCategoryId] => 28 ) @@@
33 ###
Array ( [macro_ratio] => [foodCategoryId] => 29 ) @@@
34 ###
Array ( [macro_ratio] => [foodCategoryId] => 30 ) @@@
35 ###
Array ( [macro_ratio] => [foodCategoryId] => 34 ) @@@
36 ###
Array ( [macro_ratio] => [foodCategoryId] => 35 ) @@@
37 ###
Array ( [macro_ratio] => [foodCategoryId] => 36 ) @@@
2 ~~~
1 ###
Array ( [macro_ratio] => 2.1 [foodCategoryId] => 37 ) @@@
2 ###
Array ( [macro_ratio] => 2.2 [foodCategoryId] => 2 ) @@@
3 ###
Array ( [macro_ratio] => 2.3 [foodCategoryId] => 3 ) @@@
4 ###
Array ( [macro_ratio] => [foodCategoryId] => 4 ) @@@
5 ###
Array ( [macro_ratio] => [foodCategoryId] => 5 ) @@@
6 ###
Array ( [macro_ratio] => [foodCategoryId] => 6 ) @@@
7 ###
Array ( [macro_ratio] => [foodCategoryId] => 7 ) @@@
8 ###
Array ( [macro_ratio] => [foodCategoryId] => 8 ) @@@
9 ###
Array ( [macro_ratio] => [foodCategoryId] => 9 ) @@@
10 ###
Array ( [macro_ratio] => [foodCategoryId] => 38 ) @@@
11 ###
Array ( [macro_ratio] => [foodCategoryId] => 10 ) @@@
12 ###
Array ( [macro_ratio] => [foodCategoryId] => 11 ) @@@
13 ###
Array ( [macro_ratio] => [foodCategoryId] => 12 ) @@@
14 ###
Array ( [macro_ratio] => [foodCategoryId] => 13 ) @@@
15 ###
Array ( [macro_ratio] => [foodCategoryId] => 14 ) @@@
16 ###
Array ( [macro_ratio] => [foodCategoryId] => 15 ) @@@
17 ###
Array ( [macro_ratio] => [foodCategoryId] => 16 ) @@@
18 ###
Array ( [macro_ratio] => [foodCategoryId] => 17 ) @@@
19 ###
Array ( [macro_ratio] => [foodCategoryId] => 39 ) @@@
20 ###
Array ( [macro_ratio] => [foodCategoryId] => 18 ) @@@
21 ###
Array ( [macro_ratio] => [foodCategoryId] => 19 ) @@@
22 ###
Array ( [macro_ratio] => [foodCategoryId] => 20 ) @@@
23 ###
Array ( [macro_ratio] => [foodCategoryId] => 21 ) @@@
24 ###
Array ( [macro_ratio] => [foodCategoryId] => 22 ) @@@
25 ###
Array ( [macro_ratio] => [foodCategoryId] => 23 ) @@@
26 ###
Array ( [macro_ratio] => [foodCategoryId] => 24 ) @@@
27 ###
Array ( [macro_ratio] => [foodCategoryId] => 25 ) @@@
28 ###
Array ( [macro_ratio] => [foodCategoryId] => 40 ) @@@
29 ###
Array ( [macro_ratio] => [foodCategoryId] => 41 ) @@@
30 ###
Array ( [macro_ratio] => [foodCategoryId] => 26 ) @@@
31 ###
Array ( [macro_ratio] => [foodCategoryId] => 27 ) @@@
32 ###
Array ( [macro_ratio] => [foodCategoryId] => 28 ) @@@
33 ###
Array ( [macro_ratio] => [foodCategoryId] => 29 ) @@@
34 ###
Array ( [macro_ratio] => [foodCategoryId] => 30 ) @@@
35 ###
Array ( [macro_ratio] => [foodCategoryId] => 34 ) @@@
36 ###
Array ( [macro_ratio] => [foodCategoryId] => 35 ) @@@
37 ###
Array ( [macro_ratio] => [foodCategoryId] => 36 ) @@@

我想从该数组中省略/跳过 Array ( [macro_ratio] => [foodCategoryId] => 36 ) @@@ 排序的元素意味着如果 [macro_ratio] => 为空，那么我想跳过数组的整个元素。

我正在处理的代码是：

foreach ($_POST['mealData'] as $key => $value) {
            print_r($key);
            echo " ~~~<br>";

            foreach ($value as $key => $value) {
                print_r($key);
                echo " ###<br>";
                print_r($value);
                echo " @@@<br>";
                if (isset($value['macro_ratio']) === true && empty($value['macro_ratio']) === true && isset($value['foodCategoryId']) === true && empty($value['foodCategoryId']) === true) {
                    print_r($value);
                }
            }
        }

【问题讨论】：

什么是macro_ratio？那是钥匙吗？
是的，这是关键。 print_r($value); 包含上述所有数组输出。喜欢：Array ( [macro_ratio] => 1.1 [foodCategoryId] => 37 ) Array ( [macro_ratio] => 1.1 [foodCategoryId] => 37 ) Array ( [macro_ratio] => 1.2 [foodCategoryId] => 2 ) Array ( [macro_ratio] => 1.2 [foodCategoryId] => 2 ) Array ( [macro_ratio] => 1.3 [foodCategoryId] => 3 ) Array ( [macro_ratio] => 1.3 [foodCategoryId] => 3 ) Array ( [macro_ratio] => [foodCategoryId] => 4 )

标签： php arrays multidimensional-array

【解决方案1】：

如果可行就试试这个

 foreach ($_POST['mealData'] as $key => $value) {
        print_r($key);
        echo " ~~~<br>";
        if(!empty($value['macro_ratio'])){
            foreach($value as $key2 => $value2) {
               print_r($value2);
            }
         }                

    }

【讨论】：

输出为：1 ~~~ 2 ~~~
是print_r($value2);？ 1~~~ 2~~~ 输出？
你应该使用类似的东西：if ( isset($value['macro_ratio']) && !empty($value['macro_ratio']) ) { echo $value['foodCategoryId']; } 然后再循环一次。

【解决方案2】：

macro_ratio 和 foodCategoryId 都是键，你可以在第一个循环之后访问。 if 语句将检查是否设置了 macro_ratio 并且不为空。将您的代码更改为此，它应该可以工作

$data = array( // first loop to access this level
 array( // second loop to access this level,
   'macro_ratio'    => 1.2 // check if index macro_ratio is set and not empty
   'foodCategoryId' => 2 ),
 array(
   'macro_ratio'    => 2 
   'foodCategoryId' => 4 )
)
foreach ($_POST['mealData'] as $k1 => $v1) {

 foreach ($value as $k2 => $v2) {
     check if index macro_ratio is set and not empty
    if ( isset($value2['macro_ratio']) && !empty($value2['macro_ratio']) ) {
      echo $value2['foodCategoryId'];
    }           
 }
}

【讨论】：

非常欢迎。为了便于阅读，我对代码进行了一些改进。
只是一个小技巧，不是很重要：你不需要使用 isset() 因为 empty() 也会检查变量是否存在。 php.net/manual/en/function.empty.php：P

【解决方案3】：

希望这可行...这是最简单的方法。

<?php
$result = array();
foreach ($_POST['mealData'] as $key => $value){
    if( empty($value["macro_ratio"]) )
        continue;
    else
      $result[$key] = $value;
}
var_dump($result);

【讨论】：

输出为：array(0) { }

【解决方案4】：

这是一种替代方法。在 foreach 循环之前过滤数组。 array_filter 带有自定义回调将执行此操作。

这将通过检查数组中的每个元素以确保 ['macro_ratio'] 的 length 大于 0 来返回过滤后的数组。使用 strlen 而不是 empty 仍然允许值为 0。

$filteredArray = array_filter($array, function($value) {
   return (strlen($value['macro_ratio']));
});

【讨论】：